Spring中的retry重试组件详解

    <!--springboot项目都不用引入版本号-->
    <dependency>
      <groupId>org.springframework.retry</groupId>
      <artifactId>spring-retry</artifactId>
    </dependency>
    <!--还是需要aop的支持的(如果已经引入了aop就不用再添加这个依赖了)-->
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-aspects</artifactId>
    </dependency>

    @EnableRetry
    @SpringBootApplication
    public class Application {
        public static void main(String[] args) {
            ConfigurableApplicationContext applicationContext = SpringApplication.run(Application.class, args);
        }
    }

    @Retryable(value = RuntimeException.class, maxAttempts = 5, backoff = @Backoff(delay = 100))
    public String say(String param) {
        double random = Math.random();
        if (random > 0.1) {
            throw new RuntimeException("超时");
        }
        return random + "";
    }

    @Retryable(value = IllegalAccessException.class)
    public void say() throws IllegalAccessException {
        log.info("do something... {}", LocalDateTime.now());
        throw new IllegalAccessException();
    }
    @Recover
    public void sayBackup(IllegalAccessException e) {
        log.info("service retry after Recover => {}", e.getMessage());
    }

    @CircuitBreaker(openTimeout = 5000, maxAttempts = 2,resetTimeout = 10000)
    public String get(@PathVariable Integer flag) {
        if (flag > 1) {
            log.info("重试进入");
            throw new RuntimeException("自定义异常");
        }
        return "处理正常";
    }
    @Recover
    public String getBackup(RuntimeException runtimeException) {
        log.error("重试一直失败,进入备用方法:" + runtimeException.getMessage());
        return "备用方法进去";
    }

@Slf4j
public class DefaultListenerSupport extends RetryListenerSupport {
    @Override
    public <T, E extends Throwable> void close(RetryContext context,
                                               RetryCallback<T, E> callback, Throwable throwable) {
        log.info("onClose");
        super.close(context, callback, throwable);
    }
    @Override
    public <T, E extends Throwable> void onError(RetryContext context,
                                                 RetryCallback<T, E> callback, Throwable throwable) {
        log.info("onError");
        super.onError(context, callback, throwable);
    }
    @Override
    public <T, E extends Throwable> boolean open(RetryContext context,
                                                 RetryCallback<T, E> callback) {
        log.info("onOpen");
        return super.open(context, callback);
    }
}
@Configuration
public class RetryConfig {
    @Bean
    public RetryTemplate retryTemplate() {
        RetryTemplate retryTemplate = new RetryTemplate();
        SimpleRetryPolicy retryPolicy = new SimpleRetryPolicy(); //设置重试策略
        retryPolicy.setMaxAttempts(2);
        retryTemplate.setRetryPolicy(retryPolicy);
        FixedBackOffPolicy fixedBackOffPolicy = new FixedBackOffPolicy(); //设置退避策略
        fixedBackOffPolicy.setBackOffPeriod(2000L);
        retryTemplate.setBackOffPolicy(fixedBackOffPolicy);
        retryTemplate.registerListener(new DefaultListenerSupport()); //设置retryListener
        return retryTemplate;
    }
}